International Conference on Fish Migration and Bypass Channels held in Vienna in September 1996. It covers the range of fish pass technologies currently in use throughout the world and attempts to develop a wider, more ecological perspective on this formerly engineering-orientated discipline. Emphasis is placed on enhancing an understanding of fish migration behaviour, and achieving optimum design to meet the behavioural requirements of all known migratory species. Additional attention is paid to comparing the European trend towards constructing nature-like bypass channels with the highly technical solutions dominant in North America.